Technology & Computing
Fresnel Zone Clearance Radius Calculator (60% Rule)
Calculate the first Fresnel zone radius at midpoint and the recommended 60% clearance for a wireless link.
Your inputs
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First Fresnel zone radius (midpoint)
8.036 m
Recommended 60% clearance
4.8216 m
Link distance
5 km
Frequency
5.8 GHz
Keep at least 60% of the first Fresnel zone free of obstructions (terrain, trees, buildings) to avoid significant signal degradation.
Formula and working
Fresnel radius (m) = 17.31 × √(d1×d2 ÷ (f×d)), d1/d2/d in km, f in GHz; 60% clearance recommended to avoid obstruction
- 1
Collect the inputs
Total link distance (km) = 5; Frequency (GHz) = 5.8
- 2
Apply the formula
Fresnel radius (m) = 17.31 × √(d1×d2 ÷ (f×d)), d1/d2/d in km, f in GHz; 60% clearance recommended to avoid obstruction
- 3
Result
First Fresnel zone radius (midpoint) = 8.036 m
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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